Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neruo 1 - Test 3 > Vestibular System - Lecture 12 > Flashcards

Vestibular System - Lecture 12 Flashcards

1
Q

what is the vestibular system

A

internal system used to resolve conflict

maintenance of gaze stability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what does the vestibular system do

A

senses position of your head in space

generate compensatory movements of the body to prevent falls or loss of balance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the vestibular system able to detect

A

speed changes while driving, running, etc.

side to side movement

up/down movements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

sensory conflict

A

exists b/w the 2 sensory structures

the eyes and the ears

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what does motion sickness result from

A

conflict b/w the eyes and the ears

absence of movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

overview of the flow of vestibular info

A

sensory input –> CN8 –> central processor –> motor output

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

sensory input

A

vision

proprioception

somatosensory

peripheral vestibular system (labyrinth and otoliths)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

central processor

A

vestibular nuclei
–> along with info from the cerebral cortex and cerebellum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

motor output

A

VOR (vestibular ocular reflex)

VSR (vestibular spinal reflex - balance rxns)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

peripheral vestibular system anatomy

A

size of a dime

3 semicircular canals

2 otolith organs in each ear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

semicircular canals are sensitive to

A

angular velocity as the head turns and body rotation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are the semicircular canals responsible for

A

compensatory eye movements required to maintain a stable gaze

VOR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

VOR

A

vestibular ocular reflex

to maintain a stable gaze –> eye movement must occur in a direction equal and opposite to head rotation and with equal velocity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

semicircular canal orientation

A

all canals are at 90 degree angles to each other

work in pairs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how do the canals work in pairs

A

anterior canal in one ear works with the posterior canal of the other ear

horizontal canals work together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what do the semicircular canals have connections to

A

extra ocular muscles

planes of the canals closely match the planes of extra ocular muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

parts of the semicircular canals

A

ampulla

cupula

hair cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

ampulla

A

enlargement at the end of each semicircular canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

ampulla fxn

A

sensory organ of the canals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

ampularis

A

small crest in each ampulla

21
Q

cupula

A

gelatinous mass over the crista ampularis into which hair cells project

22
Q

what occurs as the cupula bends

A

firing of the hair cells increases or decreases depending on the direction of deflection

23
Q

hair cells

A

cells location on the crista ampularis

24
Q

where do hair cells project

A

in the cupula

connect to the vestibular N (CN8)

25
Q

endolymph

A

fluid that fills the cavities of the inner ear

high in K+ and low in Na+

26
Q

perilymph

A

fluid that surround the endolymph

separated from the endolymph

high Na and low K+

similar to CSF

27
Q

endolymphatic sac

A

keeps fluid at constant level

28
Q

do endolymph and perilymph ever mix

A

not under normal circumstances

29
Q

hair cells –> firing rate

A

there is a resting firing rate of the vestibular N

30
Q

what happens if the hair cells are bent towards the side of movement

A

there is excitation

increase in the firing rate

31
Q

what happens if the hair cells are bent in the opposite direction

A

inhibition

decrease in the firing rate

32
Q

what is firing rate dependent on

A

intensity and direction of head movement

33
Q

what maintains gaze on a target when the head is moved

A

VOR - vestibular ocular reflex

34
Q

what do signals from the semicircular canals cause

A

the eyes to move in a direction equal and opposite to the head and with the same velocity

35
Q

what is the VOR mediated by

A

a reflex pathway b/w the semicircular canals and the extra ocular muscles

36
Q

abnormal VOR

A

inability to focus on objects when the head moves

37
Q

nystagmus

A

involuntary movement of the eye

normally occurs when the head is moving or following a target

38
Q

what does a nystagmus consist of

A

slow component –> when the eyes slip off a target

a fast phase –> the quick correction back

39
Q

what is the nystagmus named after

A

the quick phase

if there is weakness on one side –> the slow component is the side of the problem

40
Q

how is a nystagmus documented

A

(+) LBN

(+) RBN

41
Q

otolith

A

utricle

saccule

42
Q

fxn of otolith

A

detects linear acceleration

gravity

VSR - vestibular spinal reflex

43
Q

VSR

A

responsible for postural adjustments needed to regain balance

44
Q

otolith structure

A

macula

otoconia

45
Q

macula

A

hair cells covered by gel

46
Q

otoconia

A

calcium carbonate crystals located on the top of the gel layer that covers the macula

47
Q

what make the otolith responsible to gravity

A

weight of the crystals

48
Q

what occurs as the head moves –> otolith

A

otoconia fall to one side and cause the hair cells to fire

Neruo 1 - Test 3 (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions